Video's keep stopping + going grey screen

I searched and didn't find anything so forgive me if this has been resolved. Since the relaunch videos will randomly stop on me and the screen will become all grey. This has happened with both the archived stuff and during the live show. Refreshing the video, F5, fixes it.

I'm running the latest edition of Firefox, it's happened on Chrome too however, and have an advertised 28 mb/s connection.